startup

#!/bin/bash

# If you are looking for docs on this script, consult https://github.com/jshook/simple-startup
# or, preferably, just run ./startup

# functions
containsElement () {
  local e
  for e in "${@:2}"; do [[ "$e" == "$1" ]] && return 0; done
  return 1
}


options=$(getopt -o brg --long list -- "$@")
[ $? -eq 0 ] || { 
    echo "Incorrect options provided"
    exit 1
}
CMD="list"
eval set -- "$options"
while true; do
    case "$1" in
    --list)
        CMD="list"
        ;;
    --)
        shift
        break
        ;;
    esac
    shift
printf "CMD:%s\n" ${CMD} 1>&2
done

# locate non-relative script dir
MAIN_SCRIPT_BASEDIR="$( cd "$( dirname "${BASH_SOURCE[0]}" )" && pwd )"

# normalize path to script
MAIN_SCRIPT="${MAIN_SCRIPT_BASEDIR}/"$( basename $0 )
EXECUTION_DIR=$(dirname ${MAIN_SCRIPT})

##
## locate .startup directory
##
MAIN_SCRIPT_DIRNAME=$(dirname $MAIN_SCRIPT)
if [ "${MAIN_SCRIPT_DIRNAME}" = ".startup" ]
then export COMPONENTS_DIRNAME="${MAIN_SCRIPT_DIRNAME}"
else export COMPONENTS_DIRNAME="${MAIN_SCRIPT_DIRNAME}/.startup"
fi
MANAGED_COMPONENTS_DIRNAME="${COMPONENTS_DIRNAME}/managed-scripts"

##
## sanity check that there is only one startup script
##
if [ -f "${COMPONENTS_DIRNAME}/startup" -a -f "${COMPONENTS_DIRNAME}/../startup" ]
then
 printf "# ERROR: You must choose where to put your one and only 'startup' script.\n"
 printf "You have one in both locations below:\n%s\n%s\n" "${COMPONENTS_DIRNAME}/startup" "${COMPONENTS_DIRNAME}/../startup"
 exit 2
fi

if [ ! -d "${COMPONENTS_DIRNAME}" ]
then
 printf "# ERROR: component scripts directory '${COMPONENTS_DIRNAME}' does not exist.\n"
 exit 2
fi

##
## Initialize known component scripts array
##
component_scriptnames_ary=()

SCRIPT_DATA=$(cd $COMPONENTS_DIRNAME; /bin/ls)
while read -r line
do
 if [ "$line" = "startup.order" ] ; then continue ; fi
 if [ "$line" = "startup" ] ; then continue ; fi
 if [ "$line" = "managed-scripts" ] ; then continue ; fi
 if [ ! -x "${COMPONENTS_DIRNAME}/$line" -o ! -f "${COMPONENTS_DIRNAME}/$line" ] ; then continue ; fi
 if [ -z "$line" ] ; then continue; fi
 component_scriptnames_ary+=("$line")
done <<< "$SCRIPT_DATA"
#printf "# DEBUG: component_scriptname: %s\n" "${component_scriptnames_ary[@]}" 1>&2

managed_scripts_ary=()
if [ -d "${MANAGED_COMPONENTS_DIRNAME}" ]
then
# printf "# INFO: reading managed scripts in %s ...\n" "${MANAGED_COMPONENTS_DIRNAME}" 1>&2
 SCRIPT_DATA=$(cd ${MANAGED_COMPONENTS_DIRNAME}; /bin/ls)
 while read -r line
 do
  if [ ! -x "${MANAGED_COMPONENTS_DIRNAME}/$line" -o ! -f "${MANAGED_COMPONENTS_DIRNAME}/$line" ] ; then continue ; fi
  if [ -z "$line" ] ; then continue; fi
#  printf "# INFO: read managed script: %s\n" "$line" 1>&2
  managed_scripts_ary+=("$line")
  done <<< "$SCRIPT_DATA"
#printf "# DEBUG: component_scriptname: %s\n" "${component_scriptnames_ary[@]}" 1>&2
fi

##
## Initialize ordered components array
##
component_order_from_file=()

export ORDER_FILE="${COMPONENTS_DIRNAME}/startup.order"
if [ ! -f "${ORDER_FILE}" ]
then
 component_order_from_file=("${component_scriptnames_ary[@]}")
else
 # printf "# DEBUG: loading order file: %s\n" "${ORDER_FILE}" 1>&2
 ##
 ## Verify that component scripts referenced in the startup order are present and executable
 ##
 ORDER_DATA=$(cat ${ORDER_FILE})
 while read -r line
 do
  if [ "$line" = "startup.order" ] ; then continue ; fi
  if [ "$line" = "startup" ] ; then continue ; fi
#  if [ "${line:0:1}" = "3" ] ; then line= ${line#\#}; fi
  component_order_from_file+=("$line")
  line=${line#\#}

  if [ -x "${COMPONENTS_DIRNAME}/${line}" ]
  then COMPONENT_SCRIPT="${COMPONENTS_DIRNAME}/$line"
  elif [ -x "${MANAGED_COMPONENTS_DIRNAME}/${line}" ]
  then COMPONENT_SCRIPT="${MANAGED_COMPONENTS_DIRNAME}/${line}"
  else
    printf "# ERROR: component startup script '${line}' is not executable or it is missing.\n";
    printf "# ERROR: (it was referenced in the startup order at ${COMPONENTS_DIRNAME}/startup.order )\n";
    printf "# ERROR: (it was not found in either ${COMPONENTS_DIRNAME} or ${MANAGED_COMPONENTS_DIRNAME}\n";
    exit 2
  fi
 done <<< "${ORDER_DATA}"

 ##
 ## verify that all named components found in script form exist in the startup.order file
 ##
 for component_scriptname in "${component_scriptnames_ary[@]}"
 do
#  printf "checking %s for ordering membership.\n" "$component_scriptname" 1>&2
  if ! containsElement "${component_scriptname}" "${component_order_from_file[@]}" && ! containsElement "#${component_scriptname}" "${component_order_from_file[@]}"
  then
   printf "# ERROR: There is a startup.order file, but script '${component_scriptname}' is not listed in it.\n"
   exit 2
  fi
 done
fi
#printf "# DEBUG: component_order: %s\n" "${component_order_from_file[@]}" 1>&2

##
## warn if no component scripts found
##
if [ "${#component_order_from_file[@]}" -eq 0 ]
then
 printf "# ERROR: There are no executable scripts in ${COMPONENTS_DIRNAME}\n";
 exit 2
fi

##
## warn if order is not explicit
##
if [ ! -f "${ORDER_FILE}" ]
then
 printf "# WARNING: Component order is based on filenames.\n" 1>&2
 printf "# WARNING: Consider adding a startup.order file to control order of startup.\n" 1>&2
fi

##
## Initialize selected components array
##
selected_components_ary=()
# printf "# DEBUG: arg:[%s]\n" $* 1>&2
if [ "all" = "$1" ]
then
  printf "# INFO: selecting all components\n"; 1>&2
  selected_components_ary=("${component_order_from_file[@]}")
  printf "# DEBUG: selected from file: %s\n" "${selected_components_ary[@]}"
elif [ ! -z "$1" ]
then
  printf "# INFO: selecting specific components: $*\n"; 1>&2
  selected_components_ary=( "$@" )
  #do selected_components_ary+=("$line")
else
  printf "# INFO: You must select from the following available components, or specify 'all':\n" 1>&2
  printf "%s\n" "${component_order_from_file[@]}" 1>&2
  if [ "${#managed_scripts_ary[@]}" -gt "0" ]
  then
    managed_overrides=( "$@" )
    managed_available=( "$@" )
    for managed in "${managed_scripts_ary[@]}"
    do
      if containsElement "$managed" "${component_order_from_file[@]}"
      then managed_overrides+=("${managed}")
      else managed_available+=("${managed}")
    fi
    done
    if [ "${#managed_available}" -gt "0" ]
    then
      printf "# INFO: You may also select from managed-scripts, but they are not included with 'all':\n" 1>&2
      printf "%s\n" "${managed_available[@]}" 1>&2
    fi
    if [ "${#managed_overrides}" -gt "0" ]
    then
      printf "# INFO: The following scripts are not available from managed-scripts because they are overridden above:\n" 1>&2
      printf "%s\n" "${managed_overrides[@]}" 1>&2
    fi
  fi
  exit 0
fi
#printf "# DEBUG: selected_component: %s\n" "${selected_components_ary[@]}" 1>&2

##
## Error if selected components can not be found
##
for selected in "${selected_components_ary[@]}"
do
 if ! containsElement "${selected}" "${component_order_from_file[@]}" && \
    ! containsElement "#${selected}" "${component_order_from_file[@]}" && \
    ! containsElement "${selected}" "${managed_scripts_ary}" && \
    ! [ -x "${COMPONENTS_DIRNAME}/${selected}" ]
 then
  printf "%s was specified, but no such component could be found.\n" "${selected}"
  exit 2
 fi
done

##
## Add selected components in configured order, and log which ones are skipped
##
ordered_components_ary=()
for component in "${component_order_from_file[@]}"
do
 component=${component#\#}
 if containsElement "${component}" "${selected_components_ary[@]}"
 then
   ordered_components_ary+=("${component}")
 else
  printf "# INFO: component '%s' is being skipped\n" "${component}" 1>&2
 fi
done

for component in "${managed_scripts_ary[@]}"
do
 component=${component#\#}
 # printf "# DEBUG: component: %s\n" "${component}"
 # printf "# DEBUG: ordered_components_ary: %s\n" "${ordered_components_ary[@]}"
 # printf "# DEBUG: selected_components_ary: %s\n" "${ordered_components_ary[@]}"
 if ! containsElement "${component}" "${ordered_components_ary[@]}" && containsElement "${component}" "${selected_components_ary[@]}"
 then ordered_components_ary+=("${component}")
 printf "# INFO: including managed script after ordered scripts: %s\n" "${component}" 1>&2
 fi
done

remaining_ary=()
for selected in "${selected_components_ary[@]}"
do
  if ! containsElement "${selected}" "${ordered_components_ary[@]}"
  then remaining_ary+=("${selected}")
  fi
done
selected_components_ary=(${remaining_ary[@]})

for component in "${selected_components_ary[@]}"
do
  if [ -x "${COMPONENTS_DIRNAME}/${component}" ]
  then
    printf "# INFO: adding raw script: %s\n" "${component}"
    ordered_components_ary+=("${component}")
  fi
done

#printf "# ordered components: %s\n" "${ordered_components_ary[@]}" 1>&2

#printf "component_order_from_file: %s\n" "${component_order_from_file[@]}" 1>&2
#printf "ordered_components_ary: %s\n" "${ordered_components_ary[@]}" 1>&2

# execute components in order
for selected in "${ordered_components_ary[@]}"
do
  printf "# DEBUG: selected: %s\n" "${selected}"
  FULL_SCRIPT_PATH="UNKNOWN"
  #printf "# DEBUG: executing selected component: %s\n" ${selected}
  if [ -x "${COMPONENTS_DIRNAME}/${selected}" ]
    then FULL_SCRIPT_PATH="${COMPONENTS_DIRNAME}/${selected}"
    elif [ -x "${MANAGED_COMPONENTS_DIRNAME}/${selected}" ]
    then FULL_SCRIPT_PATH="${MANAGED_COMPONENTS_DIRNAME}/${selected}"
    else
    printf "# ERROR: selected script %s was not found.\n" "${selected}"
    exit 2
  fi

  # printf "# DEBUG: executing: %s at path: %s\n" "${selected}" "${FULL_SCRIPT_PATH}"
  export PROJECT_DIRECTORY=$(dirname ${COMPONENTS_DIRNAME})
  export SELECTED_COMPONENTS="${ordered_components_ary[@]}"
  export CURRENT_COMPONENT="${selected}"
  export COMPONENT_SCRIPT="${FULL_SCRIPT_PATH}"

  ( cd ${EXECUTION_DIR} && bash ${FULL_SCRIPT_PATH})
  last_status=$?
  if [[ last_status -ne 0 ]]
  then
   printf "# ERROR: script %s failed with status: %s\n" "${FULL_SCRIPT_PATH}" "${last_status}"
  fi
done